Legal Question in Tax Law in California

Unless you and your ex have reached a different agreement as part of a Marital Settlement Agreement, the Custodial Parent is entitled to claim the children as a deduction on taxes.

This is how the IRS defines a Custodial Parent, "The custodial parent is generally the parent with whom the child lived for the greater number of nights during the year."

If the person who the IRS defines as the noncustodial parents wants to take the children as a tax deduction, he or she must file an IRS Form 8332 (http://www.irs.gov/pub/irs-pdf/f8332.pdf) with his or her tax return.

You are going to have to calculate which one of you had the children the most nights after you separated to determine who can take the children as a deduction.